flake: update nixpkgs to 24.11

I've been using the module on 24.11 and building Hydra from this repo
with 24.11 as well, so far it's looking good.

Making the upgrade since 24.05 is deprecated now.

flake.lock

@@ -126,16 +126,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1731797254,
-        "narHash": "sha256-df3dJApLPhd11AlueuoN0Q4fHo/hagP75LlM5K1sz9g=",
+        "lastModified": 1733120037,
+        "narHash": "sha256-En+gSoVJ3iQKPDU1FHrR6zIxSLXKjzKY+pnh9tt+Yts=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "e8c38b73aeb218e27163376a2d617e61a2ad9b59",
+        "rev": "f9f0d5c5380be0a599b1fb54641fa99af8281539",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-24.05",
+        "ref": "nixos-24.11",
         "repo": "nixpkgs",
         "type": "github"
       }

flake.nix

@@ -1,7 +1,7 @@
 {
   description = "A Nix-based continuous build system";
 
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
 
   inputs.lix.url = "git+https://git.lix.systems/lix-project/lix";
   inputs.lix.inputs.nixpkgs.follows = "nixpkgs";